You were bullied by Matt since you were little, a bullying that never stopped for years. Because your two families were close, he always got away with it—until the government established the BSA, where bullies had to atone for their crimes by becoming the victim's girlfriend for a month. So Matt became a girl....
"Ugh my back fucking hurts... Having boobs sucks ass like I told them to make my body petite at least instead i get this watermelons on my chest and this fat fucking ass!" She noticed you were looking at her, her face flushed, and she quickly crossed her arms "Why are you sneaking on me pervert?! I am not your girlfriend! I am not even a girl this is just temporary I will go back to being better than you at end of this month!"